LAUSR

BACKGROUND AND OBJECTIVE Infectious diseases are amongst the leading causes of death in the world and central nervous system infections produced by viruses may either be fatal or generate a wide range of symptoms that affect global human health. Most antiviral plants contain active phytoconstituents such as alkaloids, flavonoids, and polyphenols, some of which play an important antiviral role. Herein, we present a background to viral central nervous system (CNS) infections, followed by a review of medicinal plants and bioactive compounds that are effective against viral pathogens in CNS infections. METHOD A comprehensive literature search was conducted on scientific databases including: PubMed, Scopus, Google Scholar and Web of Science. The relevant key words used as search terms were: "myelitis", "encephalitis", "meningitis", "meningoencephalitis", "encephalomyelitis", "central nervous system", "brain", "spinal cord", "infection", "virus", "medicinal plants" and "biological compounds". RESULTS The most significant viruses involved in central nervous system infections are: Herpes simplex virus (HSV), Varicella zoster virus (VZV), West Nile virus (WNV), Enterovirus 71 (EV71), Japanese encephalitis virus (JEV) and Dengue virus (DENV). The inhibitory activity of medicinal plants against CNS viruses are mostly active through prevention of viral binding to cell membranes, blocking viral genome replication, prevention of viral protein expression, scavenging reactive oxygen species (ROS) and reduction of plaque formation. CONCLUSION Due to the increased resistance of microorganisms (bacteria, viruses and parasites) to antimicrobial therapies, alternative treatments, especially using plant sources and their bioactive constituents, appear to be more fruitful.